All Ghillied Up: Easy Intel Pieces
Go to the location of the first Intel Piece, located at the top of the ladder in the first church. Get the Intel Piece and fall back down. You will die and start out getting the Intel Piece again. The Intel Piece keeps adding to the total number that you have. Repeat this process until you have 30 Intel Pieces.

Crash: Good sniping position
Note: You can do this only in multi-player matches. Go to a multi-player match at the "Crash" map. Make sure it is an Old School match. Go to the location of the helicopter crash. There is a very tall building that should be easy to identify. Climb all the way to the top of the roof. Get up onto the blue box-like "vents". Look over at the little open door where you came out of (if you went through the building, and not up the ladder). Sprint for a brief moment, then jump onto the top of that little roof object. If done properly, you should land on the roof. Jump over onto the fenced part. This is easy because the boundaries are set there, so you cannot fall off. Carefully walk up on the fence where you see a somewhat shorter building. Sprint, then jump. If done properly, you should have landed on a roof with a satellite dish. This roof has a great view over the crash and the people will have no idea where you are. This is a great spot for sniping or heavy gunning. It is probably not as useful when using SMGs.
Ned Kingsley and Dwayne Fredrick

Televisions never go off
When throwing regular and/or flash grenades at televisions that are on, they will at times still keep working even though they have been blown up.

Crossfire: Sniping location
Play the old school free 4 all section. Note the building at the very end of the map on the opposite side of the bus. Get to the very top of the building that is around the corner. Do to so, first get to the second story where the chair is found. Get on the top of the chair facing the wall and jump. You may have to run and jump, but eventually you will catch an edge. You can then work your way up to the position. Once there, go to your right. Then, jump up onto the object just past the building that you are currently on. Walk around the building, trying to stay as close to it as possible. Then, look down. Make sure you are directly above the barbed wire. Follow that until you get to the building, then jump onto it. Then, just walk across to the other building. Note: You will be floating in air. When you get there, go to the extreme left of the building. Jump and you will notice a glitch -- you are on an invisible object. Once you get there, jump again to get on top of the building. Then, go backwards but do not go off the building. Run and jump just when you get to the front edge. You will now be floating in the air. When you are almost on the fence below, you will fall. When you fall, walk directly along with the fence or else you will fall. You can just crouch and shoot people.

Have three guns
To do this trick you must have the Overkill (level 38), and the Last Stand (level 8) perks enabled. The Overkill perk should give you two primary weapons of your choice. Play a game and use this class. When you are put into Last Stand, you will get an M9. You cannot choose the pistol you want. Note: You can only use the M9 when you are in Last Stand.

Three perks
When you choose an attachment for a weapon it takes up the first perk. To stop this, select your perks then choose your weapons and attachment. You will then have three perks and a weapon attachment.

Turning televisions off
Go to any television and hold Square to turn it on or off.

if you cannot download trainer then go to Chrome/Firefox's settings, specifically to the Privacy settings and simply unchecking the "Enable phishing and malware protection" option.

Some Game Trainers are sometimes reported to be a Virus or Trojan,
the most common is a keylogger called HotKeysHook or the file
has been packed/protected with VMProtect or Themida and
is recognized as Win32/Packed.VMProtect or Win32/Packed.Themida.
In ALL cases this is a FALSE ALARM as NONE
of the Game Trainers @ GCW contain known malicious code! More info in
the PC
Games FAQ!